Yahoo yesterday released an update to Blueprint, its mobile development platform that it says now allows developers to build stand-alone Java apps, and apps for devices running Symbian and Windows Mobile. Previously the platform was limited to building mobile widgets for its Yahoo Go mobile back-end system.

Of perhaps greater appeal, the company on Wednesday unveiled a version of its oneConnect IM and SMS application for iPhone that lets users access Bebo, Facebook, Flickr, Friendster, MySpace and other social networks from that single iPhone interface. The so-called Pulse feature is part of oneConnect, a free app available at Apple's App Store.

Also new in Blueprint, according to Yahoo, is the ability to create mobile Web sites that can be viewed using HTML- or xHTML-capable mobile browsers. I'd guess such Web sites would be akin to Yahoo's own m.yahoo.com, which serves mobile devices with a Web-based interface to messaging, e-mail, news, driving directions, calendar and most of Yahoo's other applications.

"Developing applications for the fragmented mobile ecosystem...often results in developers creating an application that serves the least common denominator of mobile devices with a poor user experience, and an inability to effectively scale," said Marco Boerries, executive vice president of Yahoo Connected Life, in a statement. "Now with one click, you can write once and have mobile services run across a critical mass of devices and operating systems, potentially reaching millions of users."

In addition to oneConnect for iPhone, which leveraged the iPhone SDK, Yahoo is also using Blueprint to build other iPhone applications, and is in talks with Apple to make the platform available to iPhone developers; it gave no timetable for availability.